[Results of hematological examinations of crew members of the space vehicles EO-2, EO-3 and EO-4]. / Rezul'taty gematologicheskikh issledovanii u chlenov kosmicheskikh ékipazhei EO-2, EO-3 i EO-4.

The authors' opinion that adaptation inhibition of erythron functioning under weightlessness produces an unfavourable effect on the optimal physical state of a cosmonaut and his working capacity in the post-flight period has been confirmed by the analysis of certain hematological parameters studied in cosmonauts. The data obtained have necessitated investigation of threshold values of erythron functioning under weightlessness, and creation of artificial gravitation on board the piloted space ship to normalize erythropoiesis. Investigation of these problems of space hematology would be helpful in validation of the limits of human's long-term stay under weightlessness, and in the pre- and post-flight period management.

[Regulation of erythropoiesis in patients with iron deficiency anemia]. / Reguliatsiia éritropoéza u bol'nykh zhelezodefitsitnoi anemiei.

Erythropoietin level in the blood plasma, iron metabolism, and some erythron parameters characterizing anemia expression, erythropoiesis effectiveness and processes of hemoglobin synthesis were studied in patients with iron-deficiency anemia (IDA). The results of the investigation helped the authors to establish that hormone production in IDA patients is under the control of a feedback mechanism that is functioning at a lower level as compared to other non-renal anemias. It has been suggested that optimum possible erythron functioning in IDA patients is achieved under these conditions.

[The spatial-temporal organization of erythropoiesis in exposure of the body to hyperbaric oxygenation]. / Prostranstvenno-vremennáia organizatsiia éritropoéza pri vozdeistviiakh na organizm giperbaricheskoi oksigenatsii.

A systemic approach to appraisal of the mechanisms of changes of erythropoiesis biorhythms in stress is suggested. The authors studied the daily and seasonal rhythms of serum erythropoietin (EP) level, the production of erythrocytes (PE), the kinetics of bone marrow erythroid cells, and the activity of lipid peroxidation (LPO) and G-6-PDG in peripheral blood erythrocytes in albino rats. As a stress factor hyperbaric oxygenation initiated LPO acceleration and change of PE circadian rhythm with mesor decrease. Increased production of erythrocytes with reduction of their life span was simultaneously revealed. The differences in acrophases and amplitudes of erythropoiesis values in different seasons are caused by changes of erythroid cell kinetics due to mobilization of terminal erythropoiesis.

[Erythropoietin in differential diagnosis of erythremia and secondary erythrocytosis]. / Eritropoétin v differentsial'noi diagnostike éritremii i vtorichnykh éritrotsitozov.

The results of estimating blood plasma erythropoietic activity in patients with polycythemia of unclear genesis, in 95% of cases coincided with the clinical diagnosis proved during further follow up. These data have permitted recommendation of estimating blood plasma erythropoietic activity in patients to verify the diagnosis of polycythemic states.

[Erythropoiesis inhibitor in the plasma of patients with hemopoietic dysplasias]. / Ingibitor éritropoéza v plazme bol'nykh s gipoplaziiami krovetvoreniia.

Altogether 21 patients were examined for an erythropoiesis inhibitor contained by the IgG fraction of the blood plasma. All these patients suffered from hemopoiesis depression. The inhibitor identified in the immunoglobulin fraction of the blood plasma of 40% of the patients manifested itself at the stage of erythroid precursors of bone marrow cells. The role of the humoral inhibitor in the development of erythropoietic disorders in these patients is under discussion.

[Humoral regulators of erythropoiesis during the body's adaptation to chronic respiratory insufficiency]. / Gumoral'nye reguliatory éritropoéza v protsesse adaptatsii organizma pri khronicheskoi dykhatel'noi nedostatochnosti.

It was revealed during examination of 91 patients with chronic nonspecific lung diseases for the blood titers of erythropoietin, erythrocytic chalones, erythrocyte hemolysis products and medium molecules that in the stage I respiratory failure, there were no material changes in the titres of erythrocyte hemolysis products, erythropoietin and medium molecules, whereas the titer of erythrocytic chalones appeared to be high. Stage III of the disease was also marked by no changes in the titer of erythrocyte hemolysis products. However, the titers of erythropoietin and medium molecules rose whereas the titer of erythrocytic chalones was reduced. In the stage II respiratory failure, the above enumerated factors of humoral regulation of erythropoiesis appeared similar to those in stage I. These data evidence that different compensatory reactions to hypoxia associated with chronic respiratory failure are implicated at the molecular, cellular and systemic levels. The up-to-date treatment and diagnostic process is not feasible, provided these reactions are not taken into consideration.

[The mechanisms of the development of erythrocytosis during adaptation to dynamic muscle loads]. / Nekotorye mekhanizmy razvitiia éritrotsitoza pri adaptatsii k dinamicheskim myshechnym nagruzkam.

Dynamic muscular exercises intensified the erythropoiesis within one week and the erythrocytosis within two weeks in rats. An increase in the marrow erythroid cells proliferative activity was the basis of this reaction. The dynamics of this index coincide with the blood reticulocyte concentration dynamics. The serum erythropoietin activity was found to increase considerably. These findings suggest that erythropoietin can increase the erythroid cells proliferative activity.

[Erythron in patients with polycythemia vera during treatment by erythrocytapheresis and bloodletting]. / Eritron u bol'nykh istinnoi politsitemiei v protsesse lecheniia éritrotsitaferezom i krovospuskaniiami.

An analysis of the results of determination of erythropoietin in the blood plasma of patients with polycythemia vera and data on the kinetics of erythroid cell proliferation led to a conclusion that erythrocytapheresis more than bloodletting stimulated the production of erythropoietin and the cell proliferative potential. Activation of regenerative processes probably determined by deinhibition of the normal clone of bone marrow erythroid cells, can account for the mechanism of a therapeutic effect of erythrocytapheresis in patients with polycythemia vera.

[Effect of medium-sized molecules fro uremic serum on hemopoiesis in intact mice]. / Vliianie "srednykh molekul" uremicheskoi syvorotki na krovetvorenie intaktnykh myshei.

The effect of a medium-sized molecular fraction (3000--800) isolated from serum of patients with chronic renal insufficiency on erythropoiesis in intact mice was studied. The fraction significantly lowered the erythropoietic count of the bone marrow (maximum by 47%). The absolute number of myelocytes ranged within normal. The number of granulocytopoietic and lymphoid cells remained statistically unchanged throughout the whole experiment. The results indicate that the medium-sized molecular fraction displays activity in the stage of erythroid precursors.

[Concentration of middle-sized molecules in the blood of children with chronic renal failure during treatment with short-term hemodialysis]. / Soderzhanie molekul srednei massy v krovi detei s khronicheskoi pochechnoi nedostatochnost'iu v usloviiakh lecheniia kratkosrochnym gemodializom.

Blood serum from children and young patients with chronic kidney insufficiency at the terminal step as well as from healthy donors was fractionated using ultrafilters "Amicon" XM-50 and Sephadex G-25. Three fractions were obtained: F1--molecular mass 50,000-5,000, F3--3,000-800 (fraction of middle mass molecules, MM) and F5 < 200. Amount of protein in the MM fraction exceeded 7-10-fold the protein content in the same fraction of donor blood serum. Hemodialysis decreased dissimilarly the MM concentration in blood serum of various patients, but the content of this fraction was decreased approximately by 37% after the treatment; the constant value was obtained as a result of calculation per an hour of hemodialysis and per kg of body mass. These data suggest that elimination of the MM fraction from blood serum of patients with chronic kidney insufficiency depends on the period of the short-term hemodialysis.

[Effect of uremic serum and its fractions on stem cells in vivo]. / Izuchenie éffekta uremicheskoi syvorotki i ee fraktsii na stvolovuiu kletku in vivo.

Serum of 18 children and adolescents with chronic renal failure at the terminal stage of the kidney disease was fractionated on plates manufactured by Amicon Company and on Sephadex G-25. Uremic serum and ultrafiltrate with a molecular mass of 50,000 produced erythropoiesis inhibiting effect in polycythemic mice. However, the uremic serum and its fractions (50000--5000 and 3000--800) did not alter the number of microscopically visible colonies in the spleen of irradiated mice and their differentiation and proliferation compared to the mice that had received donor serum. Thus the inhibitory effect of serum and its fractions of patients with chronic renal failure is possible effected at the level of undifferentiated erythroid precursors producing no effect on the pluripotent stem cell.